One technique for strengthening masonry infill walls against seismic lateral forces permitted by the Turkish Seismic Code is to add a plaster layer with mesh reinforcement to one face of the wall. The study described in this paper was performed to test and analyse the effectiveness of this technique for lateral loads. In the experimental study five specimens were constructed and tested under cyclic loads. Although the inclusion of the mesh-reinforced plaster layer increased the lateral strength and stiffness of the test specimen 44 and 127%, respectively, one specimen failed prematurely because of insufficient bonding of the dowel reinforcements that were used for transfer shear loads from the frame to the plaster. Direct anchoring of the mesh reinforcement to the reinforced concrete frame instead of using dowel reinforcements in the plaster layer provided a significant improvement in the lateral strength and behaviour of the test specimens. Two alternative layers of materials such as high-strength plaster and shotcrete for improving the strength were used instead of plaster. The most successful lateral performance was obtained from the specimen in which a mesh-reinforced high-strength plaster layer was used. The lateral load-carrying capacity and stiffness of this specimen were increased up to 150 and 250%, respectively.

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The results of an experimental investigation are presented in this article for improving the shear capacity and ductility of reinforced concrete beams by using CFRP strips. The purpose of this study is to obtain ductile flexural behavior for shear-deficient reinforced concrete beams. The experimental program consisted of 10 T cross-sectioned half scale simply supported beam specimens, seven of which were constructed with deficient shear reinforcement and the remaining three without any shear reinforcement. One beam was used as a reference and nine beams were strengthened using U-shaped CFRP strips with or without fan type anchorage. Three different CFRP strip spacing such as sf = 125 mm, 150 mm, and 200 mm were used. The effect of anchorages that were used at the ends of the strips on shear strength and behavior of the strengthened specimens was investigated. CFRP strips without anchorages improved the shear strength, but no flexural behavior was observed. specimens failed with brittle shear failure due to peeling of CFRP strip from RC beam surfaces. specimens with deficient shear reinforcement that were strengthened with anchored CFRP strips showed improved shear strength and ductile flexural behavior was observed. Similar behaviors were observed for specimens even without any shear reinforcement. When the CFRP strip strains of the specimens with anchorages and without anchorages were compared, maximum strains at anchored strips were approximately 56% larger than that of without anchorages.